Over the past few years there has been a substantial movement to the use of machine readable codes in certain areas such as inventory control systems and more recently, file control systems. According to the inventory control system, where the machine reading of the codes is used for determining sales figures, the cashier will at the time of sale, machine read the code applied to the article and feed the code into a recorder for recording the sale.
Similar systems have been introduced for file control in recording the whereabouts of individual files from filing systems comprising hundreds and even thousands of files where each of the files may be handled and removed from the system by a number of people at different stations. Accordingly, it is extremely important to have a record of the station in charge of the file and of the file's location to prevent the misplacing or loss of the file. Furthermore, there are often times when an individual from one station may remove the file from the system and an individual from a second station may have an immediate need for the file. The whereabouts of the file must therefore, be recorded in a manner which permits rapid locating for retrieval of the file.
The control systems described above only work as long as the records that are kept are accurate and include a true machine reading of each coded article in the system. Where fully automated equipment provided with positioning conveyors etc., are used to read the codes, the accuracy of the system is generally acceptable. However, in many instances, the provision of fully automated equipment for both automatically positioning the article in a read position and for machine reading the code is not feasible. For instance, space restraints may be such that this equipment can not be used; the cost of such automated equipment may be prohibitive or its use may simply not be desirable in certain applications.
There is therefore, a need for an accurate machine readable code reading system that incorporates the use of a handheld reader, generally known as handheld wand. It is in such a system where the wand is manually operated that the obtaining of an accurate reading of the machine readable code can present problems. This is particularly true in light of present day technology in which available handheld wands have a narrow and precise scan field requiring accurate positioning of the wand. For example, when the machine readable code is formed from small machine readable characters such as the machine readable and optically recognizable characters of the O.C.R. set which may be in the order of 0.1 inches in height, the wand must be located such that it is within 0.1 inches of either side of the characters.